<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<input type="text" placeholder="请输入访问的网址">
<input type="button" value="访问" onclick="f1()">
<input type="button" value="三秒后访问" onclick="f2()">
<input type="button" value="刷新" onclick="f3()">
<script>
    let i=document.querySelector("input")
    function f1(){
        location.href=i.value;
    }
    function f2() {
        setTimeout(f1,3000);
    }
    function f3() {
        location.reload();
    }
</script>
</body>
</html>